Sam Writes:
Hi Steve,
Well....it's a friends bike;he wanted to do a 'period' 1/8 mile drag bike,and asked me to help.
He wanted to campaign something other than the usual(and successful) RD 250 or 350,sohe decided on an A1/A7 powerplant.We did this bike 3-4 years ago,Steve,so I'm bound to overlook a few details...but here goes-
The basis for the chassis is a spare CB160 Honda unit that I had,combined with a Suz T500swingarm and Suz T200 front end. I also had an extra Suz T125 tank,so it was cavitized toallow room for the ignition components underneath-those 160 frames are small! I addeda front downtube (4130) to secure the engine and hydraulic steering dampener. I used 18 ga304 stainless for the fuel tank located under the seat. The rear wheel is a 17" rim laced toa Yam DT something for the conical brake feature.
The ignition system was a bit of a challenge,because we used a Dyna unit that requiredfabbing a baseplate and rotor to work properly with the Kawa 1/2 speed arrangement.Cutting away the crankcases to the minimum was another time consuming task,butthere was so much material needing to be removed to achieve the right look.
The engine- is actually fairly mild in tune-the bores were later plated as I recall. A1/A7 internalshaven't been plentiful for many years,and because of this the owner sourced fresh pistons,ringsand rods for multiple sets of spares in both 250 and 350 sizes. We both have another chum thathas successfully roadraced this same type of engine,using stock internals,with very goodsuccess and longevity,so there was some 'technical encouragement' that this bike would 'work'....The chambers are some Aircone sections,rolled to the owners 'specs',and I later TIG'd themtogether.
I honestly don't know how well the bike runs,as it's been under '/continual development/' sinceit's initial completion(beat on the owner,not /me/....). One future upgrade will likely bethe addition of nitrous oxide(injected into the bottom of the crankcase,each side),asan alternative for the lack of high performance internal bits found for other,more commonengines such as the RD.I don't have any current pictures to provide you(I've asked the owner to take some),buthere are a few taken back in the early stages of the project.
I appreciate your interest,Steve.Sam
(PS- The last pic is good for a chuckle or two. Here in Indiana,there are some very ingenioussouls......able to 'transform' what appears to be a exercise bike speedo/odo into a tachometer.This 'precision instrument' was on a small RD that a friend purchased.He couldn't pass uptaking a pic of it before removing it....)
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